Cancer, also known as malignant neoplasm, is characterized by an abnormal growth of cells that display uncontrolled cell division, invasion and destruction of adjacent tissues, and sometimes metastasis to other locations in the body. There are more than 100 types of cancer, including breast cancer, skin cancer, lung cancer, colon cancer, prostate cancer, and lymphoma. Cancer is the second leading cause of death in America and it causes about 13% of all deaths. Cancer may affect people at all ages, even fetuses, but the risk for most types of cancer increases with age. Cancers can affect all animals.
Chemotherapy has become the standard of care for many cancers. Chemotherapy refers to antineoplastic drugs used to treat cancer or the combination of these drugs into a cytotoxic standardized treatment regimen. Most commonly, chemotherapy acts by killing cells that divide rapidly, one of the main properties of cancer cells. This means that it also harms cells that divide rapidly under normal circumstances: cells in the bone marrow, digestive tract and hair follicles; this results in the most common side effects of chemotherapy-myelosuppression (decreased production of blood cells), mucositis (inflammation of the lining of the digestive tract) and alopecia (hair loss). Newer anticancer drugs act directly against abnormal proteins in cancer cells; this is termed targeted therapy.
Allogeneic hematopoietic cell transplantation (HCT) can be curative for patients with leukemia and lymphomas, especially if the recipient is in complete remission at the time of transplantation. However, the risk of progressive disease or of relapse is considerably greater if the recipient is in partial remission at the time of transplantation, or if mixed rather than complete chimerism develops when non-myeloablative conditioning is used.
Despite these new agents and improved combinations, the current treatment is still not effective for many types of cancers or cancers at different stages. Improved regimens and treatments are greatly needed for cancer therapy.